ENGINE –
Cylinder Head and Valves
11-48
VALVE
(1) Check the valve face for correct contact. If incorrect, reface
using a valve refacer. Valve seat contact should be
maintained uniform at the center of valve face.
(2) If the margin exceeds the service limit, replace the valve.
Item
Standard value mm
Limit mm
Intake
1.0
0.5
Exhaust
1.5
1.0
(3) Measure valve’s total length. If measurement is less than
specified, replace the valve.
Item
Standard value mm
Limit mm
Intake
109.5
109.0
Exhaust
109.7
109.2
VALVE SPRING
(1) Measure the free height of spring and, if it is smaller
than the limit, replace.
Standard value mm
Limit mm
48.3
47.3
(2) Measure the squareness of the spring and, if the limit
is exceeded, replace.
Standard value
Limit
1.5
°
4
°
VALVE GUIDE
Measure the clearance between the valve guide and valve
stem. If the limit is exceeded, replace the valve guide or
valve, or both.
Item
Standard value mm
Limit mm
Intake
0.02 – 0.05
0.10
Exhaust
0.05 – 0.09
0.15
1EN0264
Free
height
Out of
square
Valve
guide